The genetic landscape of dural marginal zone lymphomas

The dura is a rare site of involvement by marginal zone lymphoma (MZL) and the biology of dural MZL is not well understood. We performed genome-wide DNA copy number and targeted mutational analysis of 14 dural MZL to determine the genetic landscape of this entity. Monoallelic and biallelic inactivation of TNFAIP3 by mutation (n=5) or loss (n=1) was observed in 6/9 (67%) dural MZL exhibiting plasmacytic differentiation, including 3 IgG4+ cases. In contrast, activating NOTCH2 mutations were detected in 4/5 (80%) dural MZL displaying variable monocytoid morphology. Inactivating TBL1XR1 mutations were identified in all NOTCH2 mutated cases. Recurrent mutations in KLHL6 (n=2) and MLL2 (n=2) were also detected. Gains at 6p25.3 (n=2) and losses at 1p36.32 (n=3) were common chromosomal imbalances, with loss of heterozygosity (LOH) of these loci observed in a subset of cases. Translocations involving the IGH or MALT1 genes were not identified. Our results indicate genetic similarities between dural MZL and other MZL subtypes. However, recurrent and mutually exclusive genetic alterations of TNFAIP3 and NOTCH2 appear to be associated with distinct disease phenotypes in dural MZL

Developing a new teaching approach for the chemical bonding concept aligned with current scientific and pedagogical knowledge

The traditional pedagogical approach for teaching chemical bonding is often overly simplistic and not aligned with the most up-to-date scientific models. As a result, high-school students around the world lack fundamental understanding of chemical bonding. In order to improve students' understanding of this concept, it was essential to propose a systemic treatment, namely, revising the scientific content, the pedagogical approach, and the assessment methods regarding this concept. Therefore, the main goal of this study was to build a conceptual framework that provides an advanced scientific and pedagogical foundation regarding the chemical bonding concept—one that will guide chemistry curriculum developers as well. A conceptual framework for a new teaching approach was constructed with lead-chemistry teachers, science (chemistry) educators, and research chemists. We suggest that chemical bonding should be taught based on elemental principles and by using the idea of a continuum of bond strengths. Our process includes the formulation of learning goals aligned with current scientific knowledge. Moreover, we suggest that constructing assessment tasks on carefully specified learning goals, which are described in terms of learning performances , may enable educators to foster and examine much deeper levels of students' understanding. © 2007 Wiley Periodicals, Inc. Sci Ed 91: 579–603, 2007Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/56057/1/20201_ftp.pd

Developing a hypothetical multi-dimensional learning progression for the nature of matter

We describe efforts toward the development of a hypothetical learning progression (HLP) for the growth of grade 7–14 students' models of the structure, behavior and properties of matter, as it relates to nanoscale science and engineering (NSE). This multi-dimensional HLP, based on empirical research and standards documents, describes how students need to incorporate and connect ideas within and across their models of atomic structure, the electrical forces that govern interactions at the nano-, molecular, and atomic scales, and information in the Periodic Table to explain a broad range of phenomena. We developed a progression from empirical data that characterizes how students currently develop their knowledge as part of the development and refinement of the HLP. We find that most students are currently at low levels in the progression, and do not perceive the connections across strands in the progression that are important for conceptual understanding. We suggest potential instructional strategies that may help students build organized and integrated knowledge structures to consolidate their understanding, ready them for new ideas in science, and help them construct understanding of emerging disciplines such as NSE, as well as traditional science disciplines. © 2009 Wiley Periodicals, Inc. J Res Sci Teach 47:687–715, 2010Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77521/1/20324_ftp.pd

The Effects of Internet-Assisted Chemistry Applications on Prospective Chemistry Teachers' Cognitive Structure

The aim of this study is to determine the effects of internet-assisted chemistry applications" on prospective chemistry teachers' cognitive structures. Students were requested to answer two open ended questions. Answers by each student were gathered and evaluated by flow map method. "Bonding and hybridization" subjects were taught to control group with traditional teaching method and to experimental group besides traditional method internet-assisted applications were conducted. The same open-ended questions were given to both groups and their cognitive structures were examined once more. The differences between control and experimental groups' cognitive structures were examined. (c) 2011 Published by Elsevier Ltd. Open access under CC BY-NC-ND license.WoSScopu

Teaching and learning the concept of chemical bonding

El coneixement de l'enllaç químic és essencial per comprendre gairebé qualsevol tema de química. Tanmateix, és molt difícil d'aprendre i els estudiants tenen una gran quantitat de concepcions alternatives en relació amb aquest concepte. Amb l'objectiu de millorar la comprensió dels estudiants entorn d'aquest concepte, és essencial revisar el contingut científic, l'enfocament pedagògic i els mètodes d'avaluació. En aquest article, revisem dos estudis. El primer es refereix als aspectes que han determinat les concepcions alternatives dels estudiants respecte del tema de l'estructura i l'enllaç químic, i l'altre es refereix als nous mètodes d'ensenyar el concepte enllaç químic, així com a les activitats d'avaluació.The knowledge of chemical bonding is essential to the understanding of almost every topic in chemistry. However, it is very difficult to learn, and students have a lot of misconceptions regarding this concept. In order to improve students understanding of this concept, it is essential to revise the scientific content, the pedagogical approach and the assessment methods regarding this concept. In this paper, we will review two studies. The first one will refer to aspects that have influenced students misconceptions regarding the topic of chemical structure and bonding, and the other one referring to new methods for teaching the concept of chemical bond, as well as assessment tasks